Coupling DSM-based Parallel Applications

When coupling applications running on distributed memory architectures or clusters, the coupling library must adapt to the distribution of the data in the memory of each computation node. The library must be prepared to redistribute the data when the coupled applications use different data mappings or when the number of processors of the two architectures are different. Mome is a user-level software DSM which allows programs running on a distributed memory architecture or cluster to create segments and to share data objects through memory mapping. The segments of the DSM form a simple linear address space where all shared objects of applications are allocated. The Mome coupling library accesses the data through mappings of the DSM segments on the memories of the communication threads. The parallel communication threads are distributed on the computation nodes and exploit the communication capacity of each processor. The data are moved directly between the DSM segments and the transfers do not rely on any knowledge on the application use of these segments

Le multipipeline DSPA un multiprocesseur pipeline synchronisé par les données

Disponible dans les fichiers attachés à ce documen

Coupling DSM-based Parallel Applications

When coupling applications running on distributed memory architectures or clusters, the coupling library must adapt to the distribution of the data in the memory of each computation node. The library must be prepared to redistribute the data when the coupled applications use different data mappings or when the number of processors of the two architectures are different. Mome is a user-level software DSM which allows programs running on a distributed memory architecture or cluster to create segments and to share data objects through memory mapping. The segments of the DSM form a simple linear address space where all shared objects of applications are allocated. The Mome coupling library accesses the data through mappings of the DSM segments on the memories of the communication threads. The parallel communication threads are distributed on the computation nodes and exploit the communication capacity of each processor. The data are moved directly between the DSM segments and the transfers do not rely on any knowledge on the application use of these segments

Le langage vectoriel Hellena

Disponible dans les fichiers attachés à ce documen

On-the-fly Dynamic Virtual Organizations in a Secured Grid Environment

This paper describes a system for managing dynamic collaborative workflows among business partners working in the engineering field and submitting proprietary applications to the grid. Although grid Virtual Organizations allow users from different administration domains to share resources for job submission, building static Virtual Organizations and managing the security concerns is a burden for partners who wish a short-lived collaboration. We present X-DVOs which are on-the-fly and automatically built dynamic Virtual Organizations. They manage the security configurations on behalf of grid users. In the future X-DVOs will allow business partners to automatically initiate engineering choreographies and orchestrations on geographically dispersed grid and cloud resources.Ce document décrit un système pour gérer des collaborations dynamiques entre partenaires du monde des affaires qui travaillent dans l'ingénierie et soumettent des applications propriétaires à la grille. Bien que les Organisations Virtuelles permettent aux utilisateurs de différents domaines d'administration de partager des ressources pour la soumission de travaux, la construction d'Organisations Virtuelles statiques et la gestion de la sécurité est un fardeau pour les partenaires qui souhaitent une collaboration de court terme. Nous présentons les X-DVOs qui sont des Organisations Virtuelles générées à la volée de manière automatique. Elles gèrent les configurations de sécurité à la place des utilisateurs de la grille. Dans le futur, les X-DVOs permettront aux partenaires du monde des affaires d'initier automatiquement des chorégraphies et des orchestrations sur des ressources géographiquement dispersées de la grille et des clouds

Using Open Standards for Interoperability - Issues, Solutions, and Challenges facing Cloud Computing

Virtualization offers several benefits for optimal resource utilization over traditional non-virtualized server farms. With improvements in internetworking technologies and increase in network bandwidth speeds, a new era of computing has been ushered in, that of grids and clouds. With several commercial cloud providers coming up, each with their own APIs, application description formats, and varying support for SLAs, vendor lock-in has become a serious issue for end users. This article attempts to describe the problem, issues, possible solutions and challenges in achieving cloud interoperability. These issues will be analyzed in the ambit of the European project Contrail that is trying to adopt open standards with available virtualization solutions to enhance users' trust in the clouds by attempting to prevent vendor lock-ins, supporting and enforcing SLAs together with adequate data protection for sensitive data

Multi-Cloud Portable Application Deployment with VEP

Leveraging the plethora of available Infrastructure-as-a-Service (IaaS) solutions proves to be a hard task for users who should face the complexity of dealing with heterogeneous systems, either in terms of resources or APIs. Application portability is the mean to reduce the burden of adapting applications for specific IaaS types and escape po-tential vendor lock-in. The Virtual Execution Platform (VEP) is a cloud middleware software that interfaces multiple IaaS clouds and presents end-users with an interface facilitating deployment and life cycle man-agement of distributed applications made up of several inter-networked virtual machines. This paper presents the design of VEP and experi-mental results that evaluate its scalability in deploying applications on OpenNebula and OpenStack clouds

Comparing the intestinal transcriptome of Meishan and Large White piglets during late fetal development reveals genes involved in glucose and lipid metabolism and immunity as valuable clues of intestinal maturity

Background: Maturity of intestinal functions is critical for neonatal health and survival, but comprehensive description of mechanisms underlying intestinal maturation that occur during late gestation still remain poorly characterized. The aim of this study was to investigate biological processes specifically involved in intestinal maturation by comparing fetal jejunal transcriptomes of two representative porcine breeds (Large White, LW; Meishan, MS) with contrasting neonatal vitality and maturity, at two key time points during late gestation (gestational days 90 and 110). MS and LW sows inseminated with mixed semen (from breed LW and MS) gave birth to both purebred and crossbred fetuses. We hypothesized that part of the differences in neonatal maturity between the two breeds results from distinct developmental profiles of the fetal intestine during late gestation. Reciprocal crossed fetuses were used to analyze the effect of parental genome. Transcriptomic data and 23 phenotypic variables known to be associated with maturity trait were integrated using multivariate analysis with expectation of identifying relevant genes-phenotypic variable relationships involved in intestinal maturation. Results: A moderate maternal genotype effect, but no paternal genotype effect, was observed on offspring intestinal maturation. Four hundred and four differentially expressed probes, corresponding to 274 differentially expressed genes (DEGs), more specifically involved in the maturation process were further studied. In day 110-MS fetuses, Ingenuity® functional enrichment analysis revealed that 46% of DEGs were involved in glucose and lipid metabolism, cell proliferation, vasculogenesis and hormone synthesis compared to day 90-MS fetuses. Expression of genes involved in immune pathways including phagocytosis, inflammation and defense processes was changed in day 110-LW compared to day 90-LW fetuses (corresponding to 13% of DEGs). The transcriptional regulator PPARGC1A was predicted to be an important regulator of differentially expressed genes in MS. Fetal blood fructose level, intestinal lactase activity and villous height were the best predicted phenotypic variables with probes mostly involved in lipid metabolism, carbohydrate metabolism and cellular movement biological pathways. [b]Conclusions[/b]: Collectively, our findings indicate that the neonatal maturity of pig intestine may rely on functional development of glucose and lipid metabolisms, immune phagocyte differentiation and inflammatory pathways. This process may partially be governed by PPARGC1A

Grid'5000: a large scale and highly reconfigurable grid experimental testbed

Large scale distributed systems such as Grids are difficult to study from theoretical models and simulators only. Most Grids deployed at large scale are production plat-forms that are inappropriate research tools because of their limited reconfiguration, control and monitoring capa-bilities. In this paper, we present Grid’5000, a 5000 CPU nation-wide infrastructure for research in Grid computing. Grid’5000 is designed to provide a scientific tool for com-puter scientists similar to the large-scale instruments used by physicists, astronomers, and biologists. We describe the motivations, design considerations, architec-ture, control, and monitoring infrastructure of this experi-mental platform. We present configuration examples and performance results for the reconfiguration subsystem

Installing XtreemOS on a Virtual Machine

This document describes, step by step, all actions necessary to create an XtreemOS Virtual Machine Grid from the 2.1.2 ISO with KVM and libvirt tools. A core node is first installed and configured. The second part of the document shows the installation of a resource node from the ISO and its configuration from the previously installed core node. In the last part, this resource is cloned to produce a second resource node.Ce document décrit, étape par étape, les actions nécessaires pour créer une grille de machines virtuelles XtreemOS sur KVM et libvirt à partir d'une image ISO. Une première machine de type "core" est d'abord créée puis configurée. Le deuxième partie décrit l'installation d'une machine ressource et sa configuration à partir du noeud "core" prédemment installé. La dernière section décrit le clonage de ce noeud ressource pour produire de nouvelle machines